I think i might have that Rattle too, is too late to do anything about it now(5 years old)?

You will have to ask Skoda - there's no set answer as it depends on individual circumstances. At a minimum you will have to have a full Skoda service history, and the lower the mileage the better. Also as goneoffski hints the fault will have to be fundamental (as the cam chain issue is so should qualify on that point).

Talked about it  last week with my skoda dealer,and  during the oil and filter service  they put some sensors to measure the chain(length) and said that evrythig was ok

I has worried that you were going to report back that your new shiny plugs had been replaced by the dealer as they were part of "that" service!

ok after some talk with the dealer got the replacing of the cam chain and no rattling of the engine any more in fact the engine seems to run  also better than before in terms of performance